Sound Reproduction

Table of contents

1. Front Cover
2. Half Title
3. Title Page
4. Copyright
5. Contents
6. INTRODUCTION
7. ACKNOWLEDGMENTS AND DEDICATION
8. Part One: Understanding the Principles
   1. 1 Sound Reproduction
      1. 1.1 A Philosophical Perspective
      2. 1.2 Recordings and the Music Being Recorded
   2. 2 Preserving the Art
      1. 2.1 Back to the Beginning: Capturing Sound Quality
      2. 2.2 Back to the Beginning: Direction and Space
      3. 2.3 A Circle of Confusion
      4. 2.4 Breaking the Circle: Professionals Hold the Key
      5. 2.5 Measuring the Ability to Reproduce the Art
   3. 3 Sound in Rooms—Matters of Perspective
      1. 3.1 Live Musical Performances
      2. 3.2 Sound Reproduction
      3. 3.3 Recording: Musical Instruments in Rooms
      4. 3.4 Hearing: Human Listeners in Rooms
      5. 3.5 Reflections: Conveyers, Integrators, and Differentiators of Sound
      6. 3.6 An Acoustical and Psychoacoustical Sense of Scale
   4. 4 Sound Fields in Rooms
      1. 4.1 Large Performance Spaces: Concert Halls
         1. 4.1.1 Reverberation Time and the Perception of Speech and Music
         2. 4.1.2 The Seat-Dip Phenomenon
         3. 4.1.3 The Effects of Early and Late Reflections
      2. 4.2 Offices and Industrial Spaces
      3. 4.3 Domestic Listening Rooms and Control Rooms
         1. 4.3.1 One Room, Two Sound Fields—The Transition Frequency
         2. 4.3.2 Above the Transition Frequency
         3. 4.3.3 Measuring the Lack of Diffusion in Small Rooms
         4. 4.3.4 What Is a “Small” Room?
         5. 4.3.5 Conventional Acoustical Measures in Small Listening Rooms
   5. 5 The Many Effects of Reflections
   6. 6 Reflections, Images, and the Precedence Effect
      1. 6.1 Audible Effects of a Single Reflection
         1. 6.1.1 Effects of a Single Reflection
         2. 6.1.2 Another View of the Precedence Effect
         3. 6.1.3 Reflections from Different Directions
      2. 6.2 A Reflection in the Presence of Other Reflections
         1. 6.2.1 Real Versus Simulated Rooms
         2. 6.2.2 The “Family” of Thresholds
      3. 6.3 A Comparison of Real and Phantom Images
      4. 6.4 Experimental Results with Music and Other Sounds
         1. 6.4.1 Threshold Curve Shapes for Different Sounds
      5. 6.5 Single Versus Multiple Reflections
      6. 6.6 Measuring Reflections
   7. 7 Impressions of Space
      1. 7.1 The Terminology of Spatial Perception
      2. 7.2 Listeners and Their “Preference” for Reflections
      3. 7.3 Some Reflections Are Better Than Others
      4. 7.4 Summarizing and Charting the Way Forward
   8. 8 Imaging and Spatial Effects in Sound Reproduction
      1. 8.1 First-Order Reflections
         1. 8.1.1 Some Thoughts about Loudspeaker Arrangements
         2. 8.1.2 Delayed Reflections and Reflections of Those Reflections
      2. 8.2 ASW/Image Broadening and Loudspeaker Directivity
         1. 8.2.1 Testing the Effects of Loudspeaker Directivity on Imaging and Space
         2. 8.2.2 The Audible Effects of Loudspeaker Dispersion Patterns—Other Opinions
   9. 9 The Effects of Reflections on Sound Quality/Timbre
      1. 9.1 The Audibility of Acoustical Interference—Comb Filtering
         1. 9.1.1 Very Audible Differences from Similar-Looking Combs
         2. 9.1.2 Binaural Hearing, Adaptation, and Comb Filtering
         3. 9.1.3 An Important One-Toothed Comb—A Fundamental Flaw in Stereo
      2. 9.2 Effects of Reflections on Timbre—The Audibility of Resonances
         1. 9.2.1 What Do We Hear—Spectral Bump or Temporal Ringing?
         2. 9.2.2 Where Do We Find Timbral Identity?
   10. 10 Reflections and Speech Intelligibility
       1. 10.1 Disturbance of Speech by a Single Reflection
       2. 10.2 The Effect of a Single Reflection on Intelligibility
       3. 10.3 Multiple Reflections, Noise, and Speech Intelligibility
       4. 10.4 The Effects of “Other” Sounds—Signal-to-Noise Ratio
       5. 10.5 Listening Difficulty—A New and Relevant Measure
       6. 10.6 A Real Center Loudspeaker Versus a Phantom Center
       7. 10.7 A Portable Speech-Reproduction Test
   11. 11 Adaptation
       1. 11.1 Angular Localization—The Precedence Effect
       2. 11.2 Perceptions of Distance
       3. 11.3 Sound Quality—Timbre
          1. 11.3.1 A Massive Test with Some Thought-Provoking Results
          2. 11.3.2 A Multichannel Test—And Something Is Learned
       4. 11.4 Summary
   12. 12 Adjacent-Boundary and Loudspeaker Mounting Effects
       1. 12.1 Solid Angles and the Radiation of Sound
          1. 12.1.1 Correcting for Adjacent-Boundary Effects
       2. 12.2 Loudspeaker Mounting Options
       3. 12.3 “Boundary-Friendly” Loudspeaker Designs
   13. 13 Making (Bass) Waves—Below the Transition Frequency
       1. 13.1 The Basics of Resonances
       2. 13.2 The Basics: Room Modes and Standing Waves
          1. 13.2.1 Optimizing Room Shape and Dimensions
          2. 13.2.2 Standing Waves in Real Rooms
          3. 13.2.3 Loudspeaker and Listener Positions, Different Rooms, and Manipulating Modes
       3. 13.3 Delivering Good Bass in Small Rooms
          1. 13.3.1 Reducing the Energy in Room Modes
          2. 13.3.2 Controlling the Energy Delivered from Loudspeakers to Room Modes
          3. 13.3.3 Step One: General Recommendations for Rectangular Rooms
          4. 13.3.4 Step Two: Digging Deeper for Clarification
          5. 13.3.5 Step Three: Optimizing Room Dimensions for Various Subwoofer Configurations
          6. 13.3.6 Step Four: Electronically Managing the Sound Field
          7. 13.3.7 Getting Good Bass in Small Rooms
          8. 13.3.8 Stereo Bass: Little Ado about Even Less
       4. 13.4 Looking at Time and Frequency Domains
          1. 13.4.1 “Natural” Acoustical Equalization Versus Electronic Equalization
          2. 13.4.2 Another Room, Another Problem—A Very Different Solution
       5. 13.5 Time and Frequency Domain-Measurement Resolution
          1. 13.5.1 Practical Resolution Issues—How Some Reputations Get Tarnished
   14. 14 Summary of Part One: Looking for a Way Forward
9. Part Two: Designing Listening Experiences
   1. 15 Multichannel Options for Music and Movies
      1. 15.1 A Few Definitions
      2. 15.2 The Birth of Multichannel Audio
      3. 15.3 Stereo—An Important Beginning
      4. 15.4 Quadraphonics—Stereo Times Two
      5. 15.5 Multichannel Audio—Cinema to the Rescue!
      6. 15.6 Multichannel Audio Comes Home
         1. 15.6.1 THX Embellishments
      7. 15.7 Multichannel Audio—The Ambisonics Alternative
      8. 15.8 Upmixer Manipulations: Creative and Entrepreneurial Instincts at Work
         1. 15.8.1 The Fosgate 6-Axis Algorithm
         2. 15.8.2 The Harman/Lexicon Logic 7 Algorithm
         3. 15.8.3 “Surround-Sound” Upmixing
      9. 15.9 Multichannel Audio Goes Digital and Discrete
         1. 15.9.1 Comments on Codecs
      10. 15.10 Finding the Optimum Channel/Loudspeaker Arrangement
          1. 15.10.1 Scientific Investigations Look at the Options
          2. 15.10.2 Optimizing the Delivery of Envelopment
          3. 15.10.3 Summary
      11. 15.11 Recommendations
          1. 15.11.1 The ITU Perspectives
          2. 15.11.2 Other Perspectives
      12. 15.12 Assigning the Channels and the Center-Rear Option
   2. 16 Putting Theory Into Practice: Designing a Listening Experience
      1. 16.1 The Room
      2. 16.2 Basic Video
         1. 16.2.1 The Cinema Reference
         2. 16.2.2 Transferring the Video Experience to Homes
      3. 16.3 Merging Audio and Video
      4. 16.4 Directivity Requirements for the Loudspeakers
         1. 16.4.1 Delivery of the Direct Sounds: Localization
         2. 16.4.2 L, C, R First Lateral Reflections
         3. 16.4.3 The Surround Loudspeakers—Horizontal Dispersion Requirements
         4. 16.4.4 Outside the Sweet Spot: The Effect of Propagation Loss
      5. 16.5 A Summary of Loudspeakers and the Acoustical Treatments in Rooms
         1. 16.5.1 LF, CF, and RF Loudspeakers
         2. 16.5.2 The Surround Loudspeakers
         3. 16.5.3 Propagation Loss
   3. 17 Loudspeakers I: Subjective Evaluations
      1. 17.1 The Genesis of a Life’s Work
      2. 17.2 Subjective Measurements of Loudspeakers—Turning Opinion Into Fact
      3. 17.3 Controlling the Experimental Variables
         1. 17.3.1 Controlling the Physical Variables
         2. 17.3.2 Controlling the Psychological Variables
         3. 17.3.3 Controlling the Experimental Variables
      4. 17.4 Hearing Performance in Listening Tests
      5. 17.5 Bias from Nonauditory Factors
      6. 17.6 Subjective Evaluations of Direction and Space—And More
      7. 17.7 Creating a Listening Environment for Loudspeaker Evaluations
   4. 18 Loudspeakers II: Objective Evaluations
      1. 18.1 Two Simple Source Configurations
         1. 18.1.1 Point Sources: Spherical Spreading, Near- and Far-Field Designations
         2. 18.1.2 Line Sources: Cylindrical Spreading
      2. 18.2 Measuring the Essential Properties of Loudspeakers
         1. 18.2.1 What Do We Need to Know?
         2. 18.2.2 Improved Data Gathering and Processing
         3. 18.2.3 Interpreting the Data: Exercises in Detection
         4. 18.2.4 The Relationship Between Anechoic Data and Room Curves
         5. 18.2.5 Sound-Absorbing Materials and Sound-Scattering Devices
         6. 18.2.6 The “X” Curve—The Standard of the Motion Picture Industry
         7. 18.2.7 Trouble in Paradise—The Pros Must Set an Example
      3. 18.3 Comparing the Subjective and Objective Domains
         1. 18.3.1 Measurements
         2. 18.3.2 A Contemporary Test
      4. 18.4 The Real World of Consumer Loudspeakers
         1. 18.4.1 Examples of Freestanding L, C, R Loudspeakers
         2. 18.4.2 Horizontal Center-Channel Loudspeakers
         3. 18.4.3 Multidirectional Surround Loudspeakers
         4. 18.4.4 The Perfect Surround Loudspeaker?
         5. 18.4.5 Equalizing the Surround Channels
      5. 18.5 Examples of Professional Monitor Loudspeakers
         1. 18.5.1 Professional-Audio Loudspeaker Performance Objectives
      6. 18.6 Other Measurements: Meaningful and Mysterious
         1. 18.6.1 Phase Response—Frequencies Above the Transition Zone
         2. 18.6.2 Phase Response—The Low Bass
         3. 18.6.3 The Loudspeaker/Amplifier Interface: Impedance, Wire, and Damping Factor
         4. 18.6.4 Observations on Sensitivity Ratings and Power Amplifiers
         5. 18.6.5 To Be Continued
   5. 19 Psychoacoustics—Explaining What We Measure and Hear
      1. 19.1 Loudness and the Basics of Hearing
         1. 19.1.1 Equal-Loudness Contours and Loudness Compensation
         2. 19.1.2 Equal-Loudness Contours and Deteriorated Hearing
         3. 19.1.3 Loudness as a Function of Angle
         4. 19.1.4 Basic Masking and the Auditory Reflex
         5. 19.1.5 Criteria for Evaluating Background Noises
         6. 19.1.6 The Boundaries of What We Can Hear
         7. 19.1.7 The Benefits of High-Resolution Audio
      2. 19.2 Hearing Tilts, Peaks, Dips, Bumps, and Wiggles
         1. 19.2.1 The Audibility of Resonances
         2. 19.2.2 Critical Bands, ERBN’s and Timbre
      3. 19.3 Nonlinear Distortion
      4. 19.4 Power Compression
         1. 19.4.1 Any Port in a (Turbulent) Storm?
   6. 20 Closing the Loop: Predicting Listener Preferences from Measurements
      1. 20.1 The Klippel Experiments
      2. 20.2 The Olive Experiments
      3. 20.3 An Interim Summary
   7. 21 Acoustical Materials and Devices
      1. 21.1 Key Acoustical Variables and Measurements
      2. 21.2 The Mechanisms of Absorption
      3. 21.3 Acoustical Performances of Some Common Materials
         1. 21.3.1 Typical Domestic Materials
         2. 21.3.2 Engineered Acoustical Absorbers
         3. 21.3.3 Engineered Acoustical Diffusers
         4. 21.3.4 Acoustically “Transparent” Projection Screens and Fabrics
      4. 21.4 Flutters, Zings, and the Like
      5. 21.5 Summary
   8. 22 Designing Listening Experiences
      1. 22.1 Choosing the Multichannel Delivery System
      2. 22.2 Laying Out the Room
      3. 22.3 Loudspeaker Directivity and the Acoustical Treatment of Interior Surfaces
         1. 22.3.1 Side-Wall Reflections from Front L, C, and R Loudspeakers
         2. 22.3.2 The Surround Channels and Opposite-Wall Reflections
         3. 22.3.3 Treating the Interior of a Room
         4. 22.3.4 Other Surfaces—Reverberation Time
      4. 22.4 Subwoofers, Seating and Room Dimensions
      5. 22.5 Choosing the Loudspeakers
         1. 22.5.1 Front Loudspeakers
         2. 22.5.2 Surround Loudspeakers
         3. 22.5.3 Localizing the Surround Loudspeakers, Envelopment, and Propagation Loss
         4. 22.5.4 In-Wall, In-Ceiling Options
      6. 22.6 Level and Time Adjustments and Equalization
         1. 22.6.1 Level and Time
         2. 22.6.2 Equalization
      7. 22.7 In Conclusion
10. REFERENCES
11. INDEX